1. Field of the Invention
The present invention relates to a thin film transistor array panel and a method of manufacturing the same, and more particularly, to a thin film transistor array panel used in a liquid crystal display device and a method of manufacturing the same.
2. Description of the Related Art
Generally, liquid crystal display (hereinafter, referred to as “LCD”) devices are one type of flat panel display devices. The LCD devices include two insulating substrates in which field-generating electrodes are formed and a liquid crystal layer disposed between the two insulating substrates. The LCD devices display images according to transmittance of light by rearrangement of liquid crystal molecules in the liquid crystal layer, as the intensity of the electric field to be applied to the liquid crystal layer changes.
A thin film transistor (hereinafter, referred to as “TFT”) array panel is manufactured by one or more photolithography processes using photo-resist patterns, and on a mother glass, there are manufactured a plurality of the TFT array panels.
In the large-scale LCD devices, because each active area in one mother glass is larger than the size of a mask, a divided exposure method, in which performs one or more photolithography processes are performed to form desired patterns, is needed. In this case, there has been a problem that misalignment between the patterns in the manufacturing processes occurs. This results in varying parasitic capacitances between wirings and pixel electrodes and in dislocating the patterns due to defects such as shift, rotation, distortion, etc, of the mask. As a result, these problems vary the electrical characteristics, reduce the aperture ratio and vary the brightness in the vicinity of the boundary of the TFT array panel.
Meanwhile, the pixel electrodes have been designed to overlap gate and data lines to increase the aperture ratio, and an insulating layer is formed between the pixel electrodes and the gate and data lines to reduce the parasitic capacitance therebetween. However, there are some problems that the inversed arrangement of liquid crystal molecules unintentionally generates in the vicinity of a contact hole for contacting the pixel electrodes and drain electrodes. These problems result in a leakage light and deteriorating display quality of the LCD device. More recently, there has been proposed a wider opaque film, but this structure reduces the aperture ratio and cannot obtain the aperture ratio at higher resolutions.